Open Accessgar2 is a nucleolar protein fromSchizosaccharomyces pomberequired for 18S rRNA and 40S ribosomal subunit accumulation
Author(s) -
MariePierre Gulli,
JeanPhilippe Girard,
Dan Zabetakis,
Bruno Lapeyre,
Teri Mélèse,
Michèle CaizerguesFerrer
Publication year - 1995
Publication title -
nucleic acids research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 9.008
H-Index - 537
eISSN - 1362-4954
pISSN - 0305-1048
DOI - 10.1093/nar/23.11.1912
Subject(s) - biology , schizosaccharomyces pombe , nucleolin , ribosomal protein , eukaryotic small ribosomal subunit , ribosomal rna , schizosaccharomyces , nucleolus , eukaryotic large ribosomal subunit , saccharomyces cerevisiae , 18s ribosomal rna , ribosome biogenesis , genetics , microbiology and biotechnology , gene , ribosome , rna , cytoplasm
Several nucleolar proteins, such as nucleolin, NOP1/fibrillarin, SSB1, NSR1 and GAR1 share a common glycine and arginine rich structural motif called the GAR domain. To identify novel nucleolar proteins from fission yeast we screened Schizosaccharomyces pombe genomic DNA libraries with a probe encompassing the GAR structural motif. Here we report the identification and characterization of a S.pombe gene coding for a novel nucleolar protein, designated gar2. The structure of the fission yeast gar2 is reminiscent of that of nucleolin from vertebrates and NSR1 from Saccharomyces cerevisiae. In addition, like these proteins, gar2 has a nucleolar localisation. The disruption of the gar2+ gene affects normal cell growth, leads to an accumulation of 35S pre-rRNA and a decrease of mature 18S rRNA steady state levels. Moreover, ribosomal profiles of the mutant show an increase of free 60S ribosomal subunits and an absence of free 40S ribosomal subunits. gar2 is able to rescue a S.cerevisiae mutant lacking NSR1, thus establishing gar2 as a functional homolog of NSR1. We propose that gar2 helps the assembly of pre-ribosomal particles containing 18S rRNA.